Delete Nodes From Linked List Present in Array

You are given an array of integers nums and the head of a linked list. Return the head of the modified linked list after removing all nodes from the linked list that have a value that exists in nums.

LeetCode Problem - 3217

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;        // Value stored in the node
 *     ListNode next;  // Reference to the next node in the list
 *     ListNode() {}   // Default constructor
 *     ListNode(int val) { this.val = val; }  // Constructor with value only
 *     ListNode(int val, ListNode next) { this.val = val; this.next = next; }  // Constructor with value and next node
 * }
 */
class Solution {
    // Method to remove nodes from a linked list if their values are present in the 'nums' array
    public ListNode modifiedList(int[] nums, ListNode head) {
        // Set to store unique values from the 'nums' array
        Set<Integer> uniqueNodeValue = new HashSet<>();

        // Add each value from 'nums' to the set
        for (int num : nums) {
            uniqueNodeValue.add(num);
        }

        // Create a dummy node to simplify the construction of the new list
        ListNode dummy = new ListNode(0);
        // Pointer to build the new list
        ListNode tempAns = dummy;

        // Traverse the original linked list
        while (head != null) {
            // If the current node's value is not in the set of values to remove
            if (!uniqueNodeValue.contains(head.val)) {
                // Create a new node with the current value and append it to the new list
                tempAns.next = new ListNode(head.val);
                // Move the pointer to the newly added node
                tempAns = tempAns.next;
            }
            // Move to the next node in the original list
            head = head.next;
        }

        // Return the head of the new list, skipping the dummy node
        return dummy.next;
    }
}